The invention relates to a method of preparing for a splice.
It is known to carry out a splice in order to stick material webs, in particular paper webs, to one another, primarily to stick such webs running at high speed to one another, without the machines having to be stopped in the process. This widespread technique is also referred to as the flying splice or flying reel change.
Adhesive splicing tape specifically suited for this purpose are also known and can be obtained on the market. These double-sided adhesive products, so-called splicing tapes, are generally highly adhesive and tacky, in order to permit a secure adhesive bond in the shortest possible time, and are carefully applied to the reel to be used before the actual splice, occasionally in specific geometries, in order if possible to avoid a break in the high-speed method. Preparation of the reels at rest is also desirable, in order to save the experienced specialist personnel hectic activity on the running machines.
Methods of this type, and specific adhesive splicing tapes for this purpose are known, inter alia from
EP 418 527 A2 DE 40 33 900 A1. DE 196 28 317 A1 and DE 196 32 689 A1.
However, the drawback with the previously known products and their use is that it requires considerable experience and skill on the part of the personnel in order that a reel, for example a paper reel weighing several tonnes and having a width up to 8 m, can be prepared uniformly and correctly in this way, in order to ensure a successful flying splice at speeds of several hundred metres per minute. Here, the invention is intended to provide a remedy, with particular regard to the cases in which the new reel to be equipped has damage to its upper layers and firstly has to be xe2x80x9cslabbed offxe2x80x9d, an additional problem which is widespread in practice.
Accordingly, the invention relates to a method of preparing for a splice as is characterized in more detail in the claims.
The particular advantage with this method is that it no longer requires highly qualified personnel to carry it out, and in that the web tension is maintained until the preparation has been completed and the end of the web is present in fixed form. With the method, we make the processing of the reel easier in such a way that, neither during the removal of damaged parts, so-called slabbing off, nor during any other handling of the reel, the application of the adhesive splicing tapes, the pulling off of release papers or release films from the latter, nor during the ultimate fixing of the end of the web onto the adhesive splicing tape, is the tension on the web changed, nor that the slippage of web layers occurs, with corrugations in the material, which can have a disadvantageous effect in particular in the case of paper, since then stress peaks can occur during the actual splice and easily lead to tears, without it having been possible to see this readily in the prepared paper reel.
The method according to the invention proceeds in particular as follows.
A paper reel is rotatably mounted in a reel holder (for example unwind). Underneath or at the side of the reel holder, parallel to the reel axis, there is a pressure roll. The pressure roll can be pressed against the paper reel by means of a pressure system.
The pressure roll is pivoted against the paper reel under slight pressure. The upper paper layers of the paper reel are then severed with a transverse cut. Under the influence of gravity, or with slight assistance, the cut paper ends slip off the circumference of the paper reel to the left and right. The splice tape is applied as prescribed (obliquely, straight, etc.) to the upper, undamaged paper layer. The narrow covering strip is then pulled off the splice tape. As a result of rotation of the paper reel counter to the paper running direction, the paper layer which fell off last is fixed on the splice tape under the web tension maintained by the pressure roll. The pressure roll can now be moved away. The remaining, cut-off paper webs are removed. The paper web fixed by the splice tape is then torn off (cut) exactly at the edge of the still present covering of the splice tape, and the splice preparation is completed.
An adhesive splicing tape which is particularly suitable is one according to DE 196 32689 A1, quite particularly according to DE 19628 317 A1, to which reference is expressly made for further details.